The effects of the final RTA anneal temperature on silicon/silicon germanium heterojunction bipolar transistors design rules is investigated in detail. The Si/SiGe films were deposited in a commercially available epitaxial reactor. The heterojunction bipolar transistor structure had a constant Ge profile and used non-selective, simultaneous growth of single crystal Si1-xGex on the active silicon collector and poly-crystalline Si1-xGex on the field oxide. The emitter contact opening edge to the edge of the extrinsic base implant and the edge of the extrinsic base implant to the edge of LOCOS isolation was studied by varying the spacing on the mask. Detailed electrical characterization was performed to experimentally show the effect of these design rules on device DC characteristics.